The combination did significantly better at lowering bad LDL cholesterol and other blood fats called triglycerides, as well as raising levels of good HDL cholesterol in patients with complex lipid disorders.

The late-stage data presented on Sunday at the American College of Cardiology scientific meeting in Orlando will be part of the U.S. application for a fixed-dose combination pill of the two medicines, which the drugmakers expect to submit in the second half of 2009.

Statins such as Crestor that lower LDL cholesterol are among the most widely used prescription drugs in the world. But many of the patients with high cholesterol also have high triglycerides and low levels of good HDL cholesterol, raising heart risks.

“There is a significant benefit to combining the two treatments together,” said Dr. Eli Roth, professor of clinical medicine at the University of Cincinnati College of Medicine and an investigator in the study. “You tend to correct the entire atherogenic profile.”

The 760 subjects in the Phase III trial were randomized to the standard dose of TriLipix, also known as finofibric acid, 5 milligrams of Crestor, also called rosuvastatin, or a combination of both.

After 12 weeks of therapy, the combination lowered LDL by 28.7 percent compared with 4.1 percent with TriLipix alone. It cut triglycerides by 40.3 percent compared with 17.5 percent with just Crestor. The combination raised HDL by 23 percent compared with 12.4 percent with Crestor alone.

The results were considered highly statistically significant.

“The numbers are impressive,” Roth said. “If you quizzed most physicians about what kind of changes they’d see, they would know the direction it would go but I don’t think they would know the magnitude.”

The combination also lowered levels of a key inflammation marker, known as C-reactive protein, by 28 percent, compared with 8.7 percent with only TriLipix, and 11.4 percent with Crestor alone.

There were no additional adverse events found in combining the two drugs than from the individual pills, Roth said.

“The combination is very safe,” Roth said

The planned combination pill can make it easier for doctors to help patients stay on their medicines, where they otherwise might have to juggle multiple prescriptions.

“Having two medicines in a single pill tends to make compliance on the patient’s part much better,” Roth said.

Results of combination studies using higher doses of Crestor with TriLipix were presented last June. The combination involving 5 mg of Crestor will appeal to patients who have difficulty tolerating higher doses of statins, Roth said.

Approved by U.S. regulators in December, TriLipix is the successor to Abbott’s blockbuster TriCor medicine. Both are in triglyceride lowering fibrate class of drugs, but unlike TriCor, TriLipix is approved for use with statins. Crestor is one of AstraZeneca’s top-selling medicines. (Additional reporting by Bill Berkrot; Editing by Carol Bishopric)